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        channel_name    = target_element.getAttribute('data-channel'),
        custom_css_path = target_element.getAttribute('data-theme'),
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    iframe.setAttribute('src', iframe_src);
    iframe.setAttribute('width', '100%');
    iframe.setAttribute('height', '100%');
    iframe.setAttribute('frameborder', '0');

    target_element.appendChild(iframe);
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})(window, document);